The fear for the increasing level of pollution, due both to natural causes and to the anthropic activity, makes the desire of having a pure water grow more and more.
Waste waters , both for the volumes treated and for the direct effect on the environment, play an important role in the matter of pollution, and therefore the land conservation.
For this reason, in the light of the present legislative situation, concerning the provisions for the protection of waters from pollution, our company also deals with the equipments for the treatment of waste waters.
Differently from the classic UV chambers assigned to the treatment of primary waters, for secondary waters it is necessary to have a number of lamps and a disposition of themselves, which is more suitable to the installation in this context. Such plants find an application in the final part of the treatment process, where pre-treated and filtered water, however rich in bacterial charge, needs to be disinfected.
The problem of secondary waters has not a lower importance than the one of primary waters in fact, the water coming from industrial and/or sewer discharges, directly flowing into rivers or into the sea , is a cause of the bacterial charge inside them and in the neighbouring areas.
The widespread treatments of hyper-chlorination show unquestionable problems linked to the production of DBP (Disinfection By Products). Reacting with the nitrogen compounds normally present in the polluted waters, the disinfectants with a chlorine basis give origin to a long series of undesired by-products, with mutagenic–cancerogenic features (trihalomethanes, chloramines, and so on).
On the contrary, the ultraviolet radiation is characterized by the irreplaceable advantage of having no danger deriving from overdosing.
The main technical constituents are the following:
• Low or high pressure GERMICIDAL LAMPS, according to the characteristics of the waste water to be treated. In any case all the lamps are characterized by a high ultraviolet emission in C band, with a remarkably pronounced peak on the wave length λ=254nm (maximum resonant absorption by DNA-RNA nucleic acids of the bacterial charge).
• STAINLESS STEES UV CHAMBER: For this kind of applications the use of AISI 316L stainless steel is recommended.
• RADIATION SENSOR: for the continuous monitoring of the radiation emitted by the UV lamps.
• TEMPERATURE SENSOR: For the monitoring of the water temperature (in order to prevent over-temperatures in the case of absence of flow).
• ELECTRICAL PANEL: through which it is possible to turn le germicidal lamps on, and to control instant by instant on the display, the alarm LED, the exchange contacts, the correct working of the system in its wholeness (see detailed technical sheet).
• QUARTZ SLEEVES CLEANING SYSTEM: The treatment of waste waters generates deposits on the quartz sleeves of lamps, consequently the system can be supplied with a manual or automatic cleaning system (see detailed technical sheet).
For this particolar series of equipments it does not exist a standard group in fact, considering the great variety of flow-rates and of the chemical-physical characteristics of the waters to be treated, we prefer time by time to size the system ad hoc for the specific requirements. For this reason our Technical Department is always helpful to give the customer the maximum assistance so as to identify the more suitable system for any problem. The strictly necessary data for the sizing of a UV system for waste water are:
diameter of the piping, transmittance of the water to the UV-C radiation, flow-rate to be treated. Of course, in order to operate a complete valuation we need the chemical/physical and bacteriological analysis of the water to be treated.